COCOMO is a model designed by Barry W. Boehm to give an estimate of the number of programmer-months it will take to develop a software product.

This "COnstructive COst MOdel" is based on a study of about sixty projects at TRW, a Californian automotive and IT company, acquired by Northrop Grumman in late 2002. The programmes examined ranged in size from 2000 to 100.000 lines of code, and programming languages used ranged from assembly to PL/I.

Cocomo consists of a hierarchy of three increasingly detailed and accurate forms.

  • Basic COCOMO - is a static single-valued model that computes software development effort (and cost) as a function of program size expressed in estimated lines of code.
  • Intermediate COCOMO - computes software development effort as function of program size and a set of "cost drivers" that include subjective assessment of product, hardware,personnel, and project attributes.
  • Advanced COCOMO - incorporates all characteristics of the intermediate version with an assessment of the cost driver's impact on each step (analysis, design, etc.) of the software engineering process.

One of the most important observations in the model is that personnel motivation overwhelms all other parameters. This would suggest that leadership and teamsmanship are the most important skills of all, but this point was largely ignored. Researchers would rather create tools.